if i am right,you will get the key from www area,but to go there,you must look for a dark
portal in undernet area 4,and there is a navi besides the portal saying that,if you go to
the portal,you cant jack out if you are in the www area,

You have to get the key from the keymaker. I think you have to free his brother from the
yellow ice (He may ask you to do something else. It was a long time since I finished the
game). Then go to the warpgates (the circle things north of your PC) and step on the frist
gate to the left. Then you are at Kotosqaure like magic. Underkoto is on the oppitsite
side from where you come off.